build: ensure that dash isn't prepended twice to abi version suffix

The ABIV_$(pkgname) variable already is formatted so return it as-is from
the GetABISuffix macro and only filter through FormatABISuffix if we read
the raw ABI version value from a version stamp file.

This ensures that binary intra-package dependencies on ABI versioned
libraries are properly formatted.

Ref: openwrt/packages#15871
Fixes: f6a03bf ("build: prepend ABI suffixes with a dash if package name ends with digit")
Signed-off-by: Jo-Philipp Wich <jo@mein.io>

include/feeds.mk

@@ -43,7 +43,7 @@ endef
 
 # 1: package name
 define GetABISuffix
-$(call FormatABISuffix,$(1),$(if $(ABIV_$(1)),$(ABIV_$(1)),$(foreach v,$(wildcard $(STAGING_DIR)/pkginfo/$(1).version),$(shell cat $(v)))))
+$(if $(ABIV_$(1)),$(ABIV_$(1)),$(call FormatABISuffix,$(1),$(foreach v,$(wildcard $(STAGING_DIR)/pkginfo/$(1).version),$(shell cat $(v)))))
 endef
 
 # 1: package name